鲍曼不动杆菌定植与感染鉴定方法的对照研究

目的探讨白细胞吞噬现象、细菌定量培养两种方法对鉴别鲍曼不动杆菌下呼吸道定植与感染的临床意义。方法筛选2012年6月1日至2012年12月31日入住重症医学科下呼吸道感染且下呼吸道分泌物检出鲍曼不动杆菌的患者,根据患者临床表现、CPIS评分将患者分为定植组和感染组,进行一项前瞻式队列研究,在获取培养结果后第1、3、7、9、14、16天分别采集患者下呼吸道分泌物分别进行革兰染色镜检、细菌定量培养,记录实验结果,并进行统计学分析。结果①研究期间共有38例患者入选,感染组13例,定植组25倒。感染组发现白细胞吞噬现象8例,定植组发现白细胞吞噬现象0例,两者比较差异有统计学意义（P=0．000）;感染组细菌定量培养≥10^6cFU／L有9例,定植组细菌定量培养大于10^6CFU／L的6例,两者比较差异有统计学意义（P=0．013）;②两种鉴别方法行Kappa检验,Kappa值为0．494,提示两种方法有中度相关性。结论白细胞吞噬现象和细菌定量培养可以有效判断鲍曼不动杆菌定植与感染．两者结合用来判断感染的敏感性显著提高．两种方法具有中度一致性．

A comparative study of the identification methods for colonization and infection of Acinetobacter baumannii.

Objective To investigate the colonization and infection of Acinetobacter baumannii （ A. baumannii） in lower respiratory tract using leukocyte phagocytosis test and quantitative bacterial culture assay. Methods This was a prospective cohort study. Lower respiratory tract infection patients treated from June 2012 to December 2012 whose A. baumannii culture of lower respiratory tract secretions were positive were di- vided into colonization group （ n = 25 ） and infection group （ n = 13） according to clinical manifestations and CPIS scores. On day 1,3,7,9, 14, and 16 after obtaining the cultivation results, the lower respiratory tract secretions were collected respectively. Microscopic examination and bacteri- al culture of these secretions were conducted and compared between colonization group and infection group. Results （1） Of 38 cases, leukocyte phagocytosis was found in 8 in infection group and 0 in colonization group （ P = 0. 000） ; quantitative bacterial culture results showed that patients with counts of more than 106CFU/L in infection group was 9, while it was 6 in colonization group （ P = 0. 013 ） ; （2）Kappa test of the two kinds of identification methods indicated that the Kappa value was 0. 494, suggesting a moderate correlation of the two methods. Conclusion Leukocyte phagocytosis and bacterial culture can effectively identify colonization and infection of A. baumannii. The combination of the two methods can in- crease the sensitivity for identification of infection significantly. The two methods have moderate consistency.